Geological Society of London. 283 



seemed uncertain. It appeared, however, to be derived from some other source, and 

 not to have originally belonged to the Eed Crag. In England the genus was hitherto 

 unknown in beds newer than those of Brockenhurst. The presenile of this single 

 specimen showed how much we had still to learn with regard to the Crag formation. 

 It was to be hoped that the coral might eventually be found attached to some organism 

 from which its age might be determined. 



Prof T. Hupert Jones remarked that he would be glad to hear of more corals 

 being discovered in the so-called Coralline Crag. He inquired whether coenenchy- 

 matous corals were necessarily reef-corals, observing that this coral was referred to the 

 Miocene on account of its presumed reef-forming character. He added that some of 

 the Foraminifera of the "White Crag had the aspect of existing Western Mediterranean 

 forms, and thus supported some of Prof. Duncan's remarks. 



Mr. Gwyn Jeifreys observed that the distinction between the Coralline and the 

 Eed Crag seemed to be every day diminisliing. The appearance of the fossil seemed 

 to betoken its derivative character. Like other speakers, he complimented Mr. 

 Alfred BeJl on his great intelligence in the collection of Crag fossils. 



Prof. Duncan, in reply, maintained that the differences between deep-sea and reef- 

 building corals were well established, and around modern reefs in the deeper sea the 

 forms were quite distinct, and the deep-sea corals never presented the ccenenchyma 

 distinctive of the reef-building form. This, he suggested, might be connected with 

 the difference in the amount of sea-water with which it was brought in contact, which 

 in the surf was much greater than in the almost motionless depths of the sea. 



2. " Notes on the Minerals of Strontian, Argyllshire." By Kobert 

 H. Scott, Esq., M.A., F.E.S., F.G.S. 



The paper stated that the existing lists of minerals to be found 

 at Strontian were incorrect. The discovery of apophyllite, talc, 

 and zircon, seemed to be hardly sufficiently confirmed. On the 

 other hand, Mr. Scott named several species which he had himself 

 observed in situ, and which are not noticed in any of the books, viz. 

 two felspars, orthoclase, and an anorthic felspar in the granite. 

 Two varieties of pyroxenic minerals in the granites and syenites, 

 neither of which have as yet been analyzed. Natrolite in the trap- 

 dykes, muscovite or margarodite in very large plates, lepidomelane 

 and schorl. 



Specimens of these minerals and of the others found at the mines 

 were exhibited ; but it was stated that, owing to the fact that the 

 old workings at the mines in Glen Strontian had been allowed to 

 fall in, it was now no longer possible to ascertain much about the 

 association of the species. 



One is galena, containing very little silver. The gangue is re- 

 markable for the absence of fluor and the comparative rarity of 

 blende and heavy spar. Harmotome is found principally at a miae 

 called Bell's Grove, both in the opaque variety and in the clear one 

 called morvenite, Brewsterite occurs at the mine called Middle 

 Shap, and at the mine Whitesmith Strontianite is found with Brew- 

 sterite, but without harmotome. Calcite is also very common. 



Within the last few years a new mine has been opened called 

 CoiTantee, which is in the gneiss, whereas the other mines lie on 

 the junction of the granite and gneiss. At this mine several fine 

 specimens of calcite have occurred, many of them coated with twin 

 crystals of harmotome, similar to those from Andreasberg, whereas 

 the crystals found at the old mine are not so clearly macled. 



Associated with these were found a number of small hexagonal 

 prisms, perfectly clear, and exhibiting a very obtuse dihedral ter- 



